第23期 · 垃圾食品该像烟草一样征税吗

The proposal to levy tobacco-style taxes on junk food rests on an analogy that is simultaneously powerful and imperfect. Both products impose enormous costs on public health systems; both are consumed willingly yet addictively; and both generate profits for industries that have historically obscured the damage their products cause. Yet the comparison falters in one crucial respect: whereas tobacco has no safe level of consumption, food is not a vice but a biological necessity. The challenge, therefore, is not whether to tax unhealthy food, but how to design a levy that discourages excess without punishing necessity. The case for taxing junk food is grounded in robust evidence. Mexico's 2014 sugar-sweetened beverage tax, which added roughly ten percent to the price of sodas, was followed by a six percent decline in purchases within its first year, and a twelve percent decline by the second, with the steepest drops occurring among the poorest households — precisely the demographic most vulnerable to diet-related disease. The United Kingdom's Soft Drinks Industry Levy, introduced in 2018, took a different approach: rather than taxing consumers, it penalised manufacturers based on sugar concentration, prompting reformulation across the industry. Within two years, the average sugar content of branded soft drinks in the UK fell by nearly forty-four percent, a reduction achieved not through consumer willpower but through industrial redesign. These outcomes suggest that fiscal tools, when shrewdly deployed, can alter both consumer behaviour and producer incentives in ways that education campaigns alone cannot. Nevertheless, treating junk food as though it were tobacco reveals a troubling blind spot. Tobacco is a non-essential good consumed purely for pleasure; food, even in its most processed forms, remains the means by which millions of people sustain themselves. A blunt tax on 'unhealthy food' risks being profoundly regressive, falling hardest on low-income families for whom cheap, calorie-dense products are often the only affordable option. In food deserts — neighbourhoods devoid of shops selling fresh produce — a tax on processed food effectively punishes people for circumstances they did not choose and cannot easily change. Moreover, the very definition of 'junk food' is fraught with ambiguity: is a homemade burger junk food? A whole-milk latte? A bowl of artisanal ice cream? The tobacco analogy collapses here, for no one needs to smoke to survive, and no smoker is confused about whether their habit is healthy. A far more promising approach combines targeted taxation with structural investment: subsidising fresh produce in underserved areas, restricting junk food advertising during children's programming, and reinvesting tax revenue into school meal programmes — measures that expand choice rather than merely raising its price. To conclude, I agree that fiscal measures have a role to play in addressing the public health crisis wrought by poor diet, but the tobacco model is too blunt an instrument for so nuanced a problem. A sugar levy aimed at manufacturers, modelled on the British approach, is preferable to a consumer-facing sin tax, for it drives industry reformulation without penalising the families who rely on affordable food. Ultimately, the objective is not to make junk food as expensive and socially stigmatised as cigarettes, but to make healthy food as accessible and appealing as the alternative — a goal that requires not merely taxation, but transformation of the food environment itself.